Thanks for your reply. I have changed the httpd.conf & https-ssl.conf file to the original one but still I am facing port 443 not listening issue.Even i commented the Include etc/extra/httpd-ssl.conf line but still i am getting following errors. I getting the following error all the times.In error_log, I am getting following errors,

Do you have a httpd service running plus Xampp? Thats wild, dont you know that httpd is the program name of Apache? If i got it tight, you already have Apache up and runnig, for what do you need Xampp?

If not and its all Xampp, look for the inlude of http-ssl.conf in httpd.conf and remove the surrounding ifdef SSL option. Obviously your Apache isnt startet with the option -D SSL, this should be the case. Usually this is triggered by the existence of the file /opt/lampp/etc/xampp/startssl, but for any reason that doesnt work in your installation. Did you remove files?